Pyridotriazole brighteners



3 ,058,989 Patented Oct. 16, 1962 United States Patent ()fitice hehydrogen or sulfo and Z may he hydrogen, sulfo, amino or substitutedamino, and quaternary salts thereof.

Y \N C U Q m 3,058,989 PYRIDGTRIAZOLE BRIGHTENERS Bennett G. Buell,Somerville, and Robert S. Long, Bound Brook, N.J., assignors to AmericanCyanamid Company, New York, N.Y., a corporation of Maine No Drawing.Filed Nov. 26, 1957, Ser. No. 698,930 3 Claims. (Cl. 260-296) Thisinvention relates to organ c fibers dyed with com- Pounds of TheStructure: in which Q may he 0, NH or S; U may he hydrogen or y methyland T may he hydrogen or sulfo, and quater- N nary salts thereof.

NR (5) H N in which Y may he hydrogen, alkyl, halogen, carboxy,carbalkoxy or carhoxamido, n may he one or two and R is an organicradical having a 6-rnemhered aromatic ring directly bonded to thetriazole rings, the said group R being the residue of a diazotizahleamine. This inveng lk l, l, d quaternary salts the f, tion furtherrelates to various new compounds of dilferent structures which may 'beused to dye and to brighten (6) organic fibers. More specifically, itrelates to each of the Y N N e -t' ddisti t 0 s te oudl'tedhelow:-:Dparaean ncgrupocmp 11818 /\N \I/\ Y /N\ HzN \N L N/ z \N I in whichthe hiphenyl moiety may carry one sulfonic acid group ortho to thehiphenyl bond, and quaternary salts in which Q may he 0, NH or S; and Vmay he hydroin which R may he hydrogen, halogen, alkyl, :alkoxy,thereof.

Y N N Y HzN \N \N/ D I]: \N/ N NH:

in which D and B may he hydrogen or sulfo, and quaternary salts thereof.

(8) Y N N Y Q- Q HzN \N N/ i NE: N in which 'F may be hydrogen or loweralkyl, and quaternary salts thereof. 7 (9) Y N N Y HN \NA V \N N NH:

amino, acylamino, carboxy or phenyl, R may he hydrogen, alkyl orhalogen, one of R and R not being hydrogen, and Y heing defined as abovein this "and each succeeding formula, and quaternary salts thereof.

in which M is a naphthalene ring which may carry haloand quaternarysalts thereof.

and quaternary salts thereof.

(11) Y N N \NQN/ V gen, alkyl, alkoxy and sulfo groups, and quaternarysalts thereof.

HrN

\J N X V V in which X may be hydrogen, sulfo or cyano; W may HzN 3 inwhich K and K may be hydrogen or sulfo, and quaternary salts thereof.

in which L may be hydrogen, methyl, methoxyl, or ch1 ro, andquaternary'salts thereof.

HIN

in which B is a -pyrimidyl radical, and quaternary salts HzN N N/inwhich, G and G can be the residue of an aliphatic 'amine such asethanolamine ordiethanolamine or of an aromatic amine or aminosulfonicacid, and quaternary ultraviolet, irradiation acts to neutralize theyellowish.

*color of the cloth, producing a whitening and brightening effect. Likeany dye-stufl, a necessa roperty is substantivityon the cloth.Brightencrs are applied from very dilute solution, and unless they aresubstantive on the cloth, and thus are not readily washed oi f, theeffect will not be achieved. Various types of compounds are used asbrighteners. and no. brightener is equally substantive 9n all fibers.Most brighteners are relatively nonsu-bstantive to one or another fiber,and consequently, vdiffe'rent types of brighteners must'be used fordifferent types of fabrics. Compounds which are suitable for cellulosefibers such as cotton, are often'not usable for synthetic fibers such aspolyacrylonitriles'or super-polyamides; Brighteners. which showsubstantivit'y on most common textiles are a great need in the industry.While it is possible that no single brightcner will ever becompletelyuniversal in its application, extensibe research has been done in thesearch for at leasta class of compounds which will be readily usable onany fiber f which will include members approaching universality ofapplication.

When

. V textile field for maintaining fill threads perpendicular to warpedthreads and selvages. The phosphorescent efiect allows control throughthey use of photocells'which are activated by the difference in theperiod of light emission by fluorescent compounds which phosphoresce,and those which do not. It is necessary to use phosphorescent compoundsin such weft straightening because of the almost universal use ofbrighteners in the finishing of cloth. Heretofore the control was.through the fluorescence of a thread dyed specially with a brightener,but now, with all threads being dyed with brighteners, the machine willnot operate satisfactorily. Consequently, as describedv by Allen in hisspecification, the control is now carried out by dyeing the controlthreads with a phosphorescent brightener,. which thus continues emittinglight after the source of ultraviolet is removed.

'For use in such an application, a compound must possess otherproperties besides fluorescence and phosphorescence. It is necessarythat the compound be stable to various chemical and physical treatmentswhen applied to the fiber or a fabric without losing the phosphorescentproperty and withoutbeing removed from therfiber or the fabric. Mostcompounds, even when they show some phosphorescence, do not withstandthe harsh treatment necessary in the finishing of fabrics. Suchtreatment includes caustic solution at elevated temperatures, bleachingwith hydrogen peroxide, steaming, and the like. There is thus a furtherneed in thedyestufi field fora class of compounds which willphosphoresce and also which will be stable under the harsh' treatmentsof textile manufacture. V I

We have found that organic fibers can be'dyed readily with compounds ofthe formula:.

' an organic radical having a 6-membered aromatic ring 7 directlybondedto the triazole rings, the said group R The fluorescenceofbrighteners usually ceases immetance is rapidly' increasing. Aparticularlyimportant' application for-phosphorescent compounds; isdescribed in the copending application of Eugene Allen, Serial No.

644,886, filed-March 8, 1957, now U.S.,P'atent.2,968,8516, where thephosphorescent property is used for the purfpose of .weft straightening.This is'a process in the (i.e., either of fluorescence of self coloror'dyes), theirbeing the residue of a diazotizablel. amine, and thatsuch dyed organic fibers exhibit phosphorescence and fluores cence'andare stable to the various conditions of textile manufacture. We havefurther found that these 'dyest-ufis can be applied to a great varietyof fibers, many of them being applicable to. a greater 'or lesser extentto nearly all organicfibers and that, with variations in the structure,it is possible to increase the substantivity of such compounds onspecific classes of organic fibers. We have further found severaldistinct classes of new compoundsas listed above, which form a separateaspect of our invention. 7 equivalent, their substantivity on variousfibers, their color phosphorescence and their stability to varioustreatments varying from group to group.

It is an advantage of our invention that by proper selection ofsubstituents, itis possible to obtain dyeings ona wide range of organicfibers. It is known that brighteners'tend to be substantive oncellulosic fibers when they arelinear coplanar molecules having extendedconjugation. "It is surprising however, that the. com- These classes ofcompounds are not' pounds used in our invention go on cellulosic fiberseven when these structural characteristics are not prominent. Thus,Z-phenyI-S-amino-Zfi-pyridotriazole is substantive on cotton, althoughit is not an extended linear coplanar molecule, nor is it sulfonated.However, when the substituent on the triazole ring is a simple arylgroup, one obtains optimum brightening only on polyacryloni-trilefibers. Cotton brightening is obtained more readily with the use of morecomplicated substituents on the triazole ring or, better yet, evenbis-triazoles. It is a further advantage of our invention that onereadily obtains good acid solubility with pyridotriazoles, as contrastedto benzoor naphthotriazoles. It is -a further advantage of our inventionthat the pyridotriazoles have good aifinity to many kinds of syntheticfibers, especially polyamides and polyacrylonitriles. It is a stillfurther advantage of our invention that the pyridine ring in thepyridotriazole nucleus can be quaternized with the result that increasedsolubility is obtained and afiinity is obtained on polyacrylonitrilefibers at a wire range of pHs. V

In the preparation of compounds substantive to particular fibers,attention must be given to such factors as the type of fiber to betreated, the method of application (and the solubility properties),whether the desired effect is phosphorescence of fluorescence (and iffluorescence, whether reddish-blue or greenish-blue) and similarfactors. When solubility in water is important, sulfonated aryl residuescan be used. However, 'sulfonation has the elfect of decreasing aifinityon polyacrylonitrile fibers and similar non-cellulosic fibers. Greenershades of fluorescence can be attained by using suitable auxochromicsubstituents such as alkoxyl, dialkylamino or acylamino. One of the mostuseful and at the same time most unexpected advantages of the presentinvention is the wide variety of efiects which can thus be built intothe products by proper selection of the starting materials.

The dyestuffs used in the present invention are conveniently prepared bycoupling an aromatic diazonium compound with a 2,6-diaminopyn'dine toform a 3-arylazo-2,6-diaminopyridine, which is then triazolized by anoxidative ring closure method using a mild oxidizing agent. If it isdesired to quaternize, this is achieved by reacton of the triazoleproduct with an alkylating agent such as an alkyl halide. Variousaromatic amines may be used to form the diazo component in the firststep of this preparation and proper selection of the amine makes itpossible to produce an optical bleaching agent with properties making itsuitable for use on various textile fibers. Examples of diazotizableamines which may be used in the reaction to produce compounds of theinvention are:

Aniline p- And m-aminobenzoic acid Alkyl and aryl pand m-aminobenzoatesp- And m-aminobenzenesulfonic acid and their alkyl and aryl esters p-And m-aminobenzenealkyl sulfones p- And m-aminoacetanilide p- Andm-aminobenzanilide p- And m-aminoanisanilide p- And m-aminobutyranilidep- And m-toluidine p- And m-chloroaniline p- And m-bromoaniline p- Andm-fluoroaniline o-Xylidine (3,4-dimethylaniline) p- And m-anisidine p-And m-nitroaniline 4-aminobiphenyl Benzidine 4-aminostilbene4,4'-diaminostilbene-2,2-disulfonic acid Z-naphthylamineZ-aminonaphthalene-6-sulfonic acid Z-aminonaphthalene-S-sulfonic acid2-aminonaphthalene-S,7-disulfonic acid 2-aminonaphthalene-6,S-disulfonicacid Z-(p-arninophenyl)-benzimidazole, benzoxazole and benzothiazole 5-And 6-arninobenzoxazole, -benzothiazole, -benz.imidazole, -benzothia2ole4-aminopyridine 3-aminopyridine 6-methoxy-2-naphthylamine6-chloro-2-naphthylamine These diazos are coupled with various2,6-diaminopyridines such as the following:

2,6-diaminopyridine 2,6-diamino-3-methylpyridine2,6-diamino-4-methylpyridine 2,6diaminopyridine-4-carboxylic acid andits esters 2,6-diamino-3-bromopyridine 2,6-diamino-4-brornopyridine2,6-diaminopyridine-4-carboxamide The 3-arylazo-2,o-diaminopyridineintermediate is then oxidized with a mild oxidizing agent such as air inthe presence of copper sulfate, which results in ring closure to thetriazole derivative.

Pyridotriazoles in which the substituent on the triazole ring is apara-aminophenyl radical forms an especially useful class of compoundsfor use in our invention, since they can be intermediates for thefurther preparation of more complicated brighteners and phosphorescentagents which can also be used in our invention. For example, the aminogroup on this phenyl ring can be diazotized and coupled into othercoupling components and, when the coupling component is so constitutedthat an o-aminoazo compound is formed, this too can be triazolized togive a bisor poly-triazole deritoo can be triazolized to give a bisorpoly-triazole derivative. Thus a tbis-triazolo compound, eithersymmetrical or unsymmetrical is readily produced. The symmetricalbis-triazolo compounds are also readily produced from tetrazotization ofan aromatic diamine.

The fibers which may be used in preparing the dyed fibers of ourinvention include the various organic fibers used in the textileindustry, both synthetic and natural, since substantivity and otherproperties can be varied by the choice of the proper substituents andthe proper ring groupings in the brightener molecule to favorsubstantlVl ty on any particular type of fiber. Among the fibers whichmay be used are the natural fibers, both cellulosic and non-cellulosic,such as cotton, wool, silk, and the hke, and the synthetic fibers ofboth the cellulosic and non-cellulosic types such as viscose rayon(i.e., regenerated cellulose) cellulose esters such as celluloseacetate, polyacrylonitrile (either the homopolymer or copolymers withvarious comonomers such as vinyl pyridine, methyl acrylate, vinylchloride, and the like), superpolyamides such as hexamethylenepolyadipamide and poly-omegaaminocaproamide, and superpolyesters such aspolymeric glycolterephthalate.

T 'he brighteners to be used in our invention are especially useful onthose fibers for which most known brighteners have been notsatisfactory, such as the polyacrylics and the superpolyesters.

The brighteners may be applied as optical bleaching agents or asphosphorescent agents from detergent compositions as ordinarilyformulated in the art, or from rinsing liquors for treatment duringtextile manufacture or after laundering operations.

In addition to being useful as brightening agents, the products used inthe preparation of our invention are also phosphorescent and thus thedyed fibers of our invention can be used where phosphorescence isimportant for special effects. 2-phenyl6-aminopyridotriazole isespecially useful for this purpose because of its phosphoresence and itssubstantivity to a wide variety of 7 phosphorescent dyed fibers isdescribed in the copending application of Eugene Allen Serial No.644,886, filed March 8, 1957, now US. Patent 2,968,856, where the3,4-dichloroaniline 3-ch1or-p-anisi'dine m-Br'omaniline, and the like.

8 The amines which can beused to prepare the compounds of the structure:

phosphorescent property is utilized for the purpose of p WeftStraightening, a process in the textile field for N CH=OHZ maintainingfill threads perpendicular to warp threads and zN \N V v I selvages. 'Asdescribed above, it is necessary forsuch ap- X W Plication to havecompounds which l Stand rather include 4- aminostilbene,4-aminostilbene-2,2-disulfonic drastic treatment. It is an advantage ofthe dyed fibers of id; 4 i fl gt f fi acid, g '-4e i our invention thatthey are able to withstand the treatilb 4- i -4' it fi1b 2 2 di lf iacid, 2- ment with caustic solution at elevated" temperatures and V (4 ifilb l) th l ulf andflle m similar drastic treatments, and that theyshow sufiicien The ami s which may be used to prepare the class ofphosphorescence. 7 compounds of the formula:

Our invention includes not only organic fibers dyed V 7 with a broadclass of pyridotriazole compounds, but also Y I N N U specific groupsfalling within this broad class of com- 7 pounds which have distinct andseparate properties. These V are all prepared in the same manner asdescribed in gen- HZN N eral for the class, i;e., by the coupling of anaromatic N Q T diazo compound into a 2,6-diaminopyridine. Thus, in V 7each class the pyridines which may be used as the starting includedehydrothiotoluidine, dehydrothiotoluidine sulmaterial are the same, butthe diazotizable amine which fonic acid, 4-amino-2-phenyl benzoxazoie,4-amino-2- is used varies with the class of compounds beingConphenyl-benziamidazole, and the like. sidered. In the preparation ofcompounds of the class:

"In the class of compounds of the structure: Y N

Y N e r Y KY 3 HEN N e R: V V the amino compounds which may be used asstarting mathe following amines may be used; 5- or-6-aminobenzo- 1 i dthiazole, Z-methyl-S- or 6-aminobenzothiazole, '2-phenyl- Ch} 5- or6-aminobenzothiazole, 5- or' 6-aminobenzoxoazole, f i ne 2-phenyl5- or6-aminobenzoxoaz-ole, 2-methyl-5- or 6- Pi i arninobenzoxoazoles, 5aminobenzimidazole, Z-methyl- P' m P? 5 (6) -arninobenzimidazole,2-phenyl-5 (6 -aminobenzimidp-Phenetidme a p awe and the like.p-Nltroanrhne f a r ppfienylenediamine L V 40 In the preparation orcompounds of the structure. Monoacylatcd'p-phenylenediamines; such asp-acetamido- Y Y aniline N r r r a p-Benzanndoanilmep-Propionylamidoaniline, and' the like M 1 p-Aminobenzoic acid HzN4-aminodiphenyl N i 5553 3: the starting material which is, used asthe'diazotizable 4chlor-3'-butylaniline g amine may be benzidine or abenzidlne monosulfonic acid in which the sulfonic acid group is ortho tothe biphenyl bond;

Compounds'of the type: 7 V

repeated. These products are yellow fluorescent dyes.

Compounds of the structure:

[The amines which may be used-to prepare compounds ofthe class of thestructure:

Y N c 7 Y include beta-naphthylamine, Z-aminonaphthalene-6-suli/ fonicacid, Z-aminonaphthalene-S-sulfonic acid,Z-aminonaphthalene-4,6-disulfonic acid, 2-aminonaphthalene-5,7- Hm NH:disulfonic acid, Z-arhinonaphthalene-6,8-disulfonic acid, 2- \N N a N Naminonaphthalene-4,8-disulfonic acid, 6-methoxy-2-naphthylamine,6-chloro-2 naphthylamine, and the like;

can be prepared starting with such compounds as4,4'-diaminodiphenylamine, 4*,4-dia'minodiphenyl methyl amine,

4,4'-diaminodiphenyl ethyl amine, 4,4-diaminodiphenyl butyl amine, andthe like.

The starting material for compounds of the structure:

is 3,7-diamino-dibenzothiophene-S,5'-dioxide.

Compounds of the formula:

are prepared from 4,4diamino-N,N'-diphenylurea.

Compounds of the structure:

the like.

The compounds of the structure:

N r L A in which L may be hydrogen, methyl, methoxyl, or chloro, aresimilarly prepared by a second diazotization and coupling andtriazolization, this time by coupling into 6- amino-S-substitutedZ-para-sulfophenyl benzotriazole and performing a second triazolization.The substituent on the coupling component for the second triazolizationcan be hydrogen, methyl, methoxyl or chloro.

Compounds of the type:

in which B is a S-pyrimidyl nucleus are obtained by coupling adiazotized amino pyrimidine into a 2,6-diamino pyridine andtriazolizing. For this purpose one can use S-amino pyrimidine,substituted S-amino pyrimidines, and the like.

p to Compounds of the type:

are prepared by reacting the intermediate2-p-aminophenyl--amino-pyridotriazole with cyanuric chloride, followedby further reaction of the product with aliphatic amines such as alkylamines or preferably substituted alkylamines (ethanolamine,diethanolamine, morpholine, etc.) or with aromatic amines orarninosulfonic acids such as aniline, sulfanilic acid, and the like.

In all these various classes of dyestuffs, as well as in the principalinvention of the dyed fibers, the pyridine ring in the pyridotriazolemoiety can be quaternized by treatment with an alkylating agent to forma quaternary compound on the pyridine ring nitrogen. Examples ofalkylating agents which may be used are methyl iodide, ethyl bromide,butyl bromide, benzyl bromide, dimethyl sulfate, diethyl sulfate,ethylene chlorohydrin, beta-diethylamino ethyl chloride, alkyl tosylatessuch as methyl tosylate, and the like. Among the purposes of suchquaternization are to get increased water solubility of the brightenermolecule and to permit the application of the dyestuif over a broaderrange of pH. The quaternized brighteners are in general equivalent tothe unquaternized brighteners, and in some cases superior, insubstantivity to various fibers. Consequently, the quaternized compoundsand the fibers dyed with them form a part of our invention.

Our invention can be illustrated by the following examples in whichparts are by weight unless otherwise indi cated.

Example 1 A mixture of 27.9 parts of 2,6-diamino-3-phenylazopyridine(commercially available as Pyridium or Azoimide), 450 parts of ethanol,70 parts of Water and 180 parts of concentrated ammonium hydroxide isheated under reflux with stirring. A hot solution of 170 parts of coppersulfate in 500 parts of water and 300 parts of concentrated ammoniumhydroxide is added. After heating for several hours, an additionalportion of 25 parts of copper sulfate in parts of Water and 45 parts ofconcentrated ammonium hydroxide is added and heating is continued untilthe reaction is substantially complete, as shown by disappearance of thestarting material. After cooling the mixture, the product is removed byfiltration and Washed thoroughly with dilute ammonium hydroxide andWater to remove the copper. The product is purified by dissolving in 400parts of water, 450 parts of ethyl alcohol, and parts of concentratedhydrochloric acid. After treatment with a decolorizing agent andfiltering, the filtrate is treated with 55 parts of concentratedhydrochloric acid. On cooling, the hydrochloride of the productseparates as a cream-colored rods and is removed by filtration andWashed with alcohol.

' 11 Example 2 HQY \N \N/ sO Na hydroxide and 20 parts of Water. Themixture is heated to the boiling point and a hot solution of 17 parts ofcopper sulfate, 75 parts of water, a'nd36 parts of concentrated ammoniumhydroxide is added and the mixture is heated at the reflux temperaturewith stirring until the reaction is complete. After the mixture iscooled, the solid is removed by filtration, slurried in dilutehydrochloric acid and then again isolated by filtration. purification,it is dissolved in methyl Cellosolve containing a small amount of sodiumhydroxide and after clarification with a decolorizing agent, the productis isolated from the filtrate by adding additional sodium hydroxidesolution and saturated sodium acetate. After stirring, the product isisolated as a light tan sodium salt.

' Example 3 N NQ'SOaNH HzN The procedure of Example 2 is followed,except than an equivalent quantity of sulfanilic acid is" substitutedfor the 4-aminostilbene-2-sulfonic acid. The product is obtained as analmost white sodium salt.

acid at 30 C. The diazonium. solution is combined with a solution of2.18 parts of 2,6-diaminopyridine in 100 parts of acetic acid, 100 partsof water, and 4'parts of concentrated hydrochloric acid. With stirring,75 parts of saturated sodium acetate solution is added. The mixtureisstirred until the coupling is complete and the-light orange couplingproduct is removed by filtration and; triazolized by oxidation withcopper sulfate and ammonium hydroxide as described in Example 2. Theproductis purified by dissolving in about .600 parts of hot methylCelloso1ve and excess concentrated hydrochloric 'acid', clarifying witha decolorizing agent and isolating by the addition. of 300 parts ofwater and excess ammonium hydroxide to the filtrate.

Example The procedure of Example 4'is followed except that an equivalentquantity of 2,6-diamino 3-ibromopyridine is used in place of the2,6-diaminopyn'dine and an equivalent quantity of aniline is used inplace of the 4-aminobiphenyl. The corresponding methyl compound isprepared by star-ting with 2,62-diamino-3-methylpyridine.

Example 6 The procedure of Example 4 is followedexcept than anequivalent quantity of 2,6-diamino-4-picoline is used For" in place ofthe 2,6-diaminopyridine.

Example 7 A diazonium solution is prepared by diazotizing 13.8 parts of4-nitro aniline with sodium nitrite. The solution is combined with asolution of 10.9 parts of 2,6-diaminopyridine in 500 par-ts of aceticacid, 500 parts of water and 18 parts of concentrated hydrochloric acid.With stirring, the mixture'is neutralized with saturated sodium acetatesolution and the bright red o-aminoazo product which forms is removed byfiltration and washed with water. This o-aminoazo product is taken up in540 parts of-ethanol, 150 parts of water, and 135 parts of concentratedammonium hydroxide. The mixture is heated and a hot solution of 125parts of copper sulfate, 500 parts of water, and 225 parts of ammoniumhydroxide is added. The mixture is heated atthe'reflux temperature untilthe triazolization is complete, cooled, and the product is removed byfiltrationp This nitro compound is then reduced to the correspondingamino compound by the following procedure: 7

The nitro compound is added to 150 parts of water, parts of ethanol and,120 parts of 5 N sodium hydroxide. To the mixture at 70-85" C. is added70' parts of sodium hydros ulfite. I After stirring and cooling, the

' droxide.

' product is isolated by filtration and washed alkali-free with water.The-amino compound is purified by clarification with a decolorizingagent from solution in 250 parts of hot 4 N hydrochloric acid, andisolated by making the filtrate alkaline by the addition of ammonium hy-Example 8 By the use of equivalent amounts of other acyl halides inplace of the p-anisoyl chloride such as acetyl chloride, butyrylchloride, stearyl chloride, benzoyl chloride, 2,4- dichlorobenzoylchloride, and similar compounds, the corresponding acylamide compoundsare obtained.

Example 9 N N \r p \N N/ SO21 a HzN \N/ N/ C \N A diazonium solutionprepared by diazotizing 2.26 parts of 6-amino-2-(p-aminophenyl)-2-pyrido2,3-d-v-triazole (prepared as in Example 7) is combined With a slurry of2.54 parts of sodium naphthionate in 100 parts of Water, 4 parts ofhydrochloric acid and 50 parts of acetic acid. With stirring, 50 partsof saturated sodium acetate solution is added and the stirring iscontinued until the coupling is complete (4 hours). The o-aminoazoproduct is removed by filtration and triazolized by oxidation using theprocedure described in Example 7. Purification of this bis-triazolylproduct is effected by dissolving the product in 400 parts of hotmonoethanolamine, and 4 parts of N sodium hydroxide solution. Afterclarification with a decolorizing agent, 100 parts of Water is added tothe filtrate and the sodium salt of the product is salted out by theaddition of sodium hydroxide, given a crystalline yellow product.

Example 10 A tetrazonium solution prepared by tetrazotizing 1.86 partsof benzidine in 100 parts of water, 9 parts of hydrochloric acid and 8parts of l N sodium nitrite solution is combined with a solution of 2.4parts of 2,6-diaminopyridine in 100 parts of water and 5 parts ofconcentrated hydrochloric acid. The mixture is neutralized to Congo redindicator by addition of saturated sodium acetate solution (about 60parts). The color changes from blueblack to dull orange. After stirringthe mixture, the solid azo product is removed by filtration.

For conversion to the triazole derivative the disazo product from aboveis slurried in a hot mixture of 150 parts of pyridine and parts ofconcentrated ammonia. A half-portion of a solution of 24 parts of coppersulfate, 100 parts of water and 40 parts of ammonia is added and themixture is heated for several hours. The other half of the coppersulfate solution is then added and the mixture is heated until thereaction is complete. The solid materialis removed by filtration andpurified by recrystallization from about 300 parts of N-rnethyl-Z-pyrrolidone.

Example 1] 'of 200 parts of ice and 16 parts of hydrochloric acid.

After stirring for a short period, the excess nitrite is de stroyed withsulfamic acid.

To the above brown slurry is added a solution of 2.4 parts of2,6-diamino-pyridine in 150 parts of Water and 5 parts of concentratedhydrochloric acid. Saturated sodium acetate solution is added until themixture is neutral to Congo red indicator.

1 1 rapidly and after stirring, the solid disazo compound is removed byfiltration and triazolized by the procedure described below.

The solid product is dissolved in a hot mixture of parts of pyridine and20 parts of ammonium hydroxide. To this is added a half portion of asolution of 24 g. copper sulfate, 100 parts of water and 20 parts ofconcentratedammonia. After heating a short period, the second halfportion of the copper sulfate solution is added and the mixture isheated until the reaction is complete. The solid bis-triazolo compoundis removed by filtration.

The product may be purified by recrystallizing from hot dimethylformamide containing a small amount of caustic and then precipitatingthe product from the cooled dimethylformamide filtrate by addition ofWater and hydrochloric acid to the neutral point.

Example 12 SOaNa A diazonium solution prepared by diazotization of 2.26parts of 6-amino-2-(p-aminophenyl)-2-pyrido 2,3-d-v-triazole with sodiumnitrite in hydrochloric acid solution is combined with a solution of3.04 parts of 6-arnino- 2H-5-methyl-2-(p-sulfophenyl)-benzotriazole inparts of acetone, 100 parts of water and 4 parts of concentratedhydrochloric acid. With stirring, 50 parts of saturated sodium acetatesolution is added and the mixture is then stirred until the coupling iscomplete (4 hours). The resulting o-aminoazo product is removed byfiltration and then triazolized by oxidation with copper sulfate usingthe procedure described in Example 6. The product is isolated as thesodium salt and purified by treatment with decolorizing charcoal in hotdimethyl formamide solution, giving the product as the purified sodiumsalt.

Example 13 (30011 The procedure of Example 1 is followed except that anequivalent amount of 2,6-diaminopyridine-4-carboxylic acid is used inplace of the 2,6-diaminopyridine.

N NH2 Example 14 corresponding substitution: para-toluidine,para-anisidine,

para-butylaniline, para-propylaniline or para-aminoben- Coupling takesplace 75 Zoic acid.

a the 4-aminobiphenyl.

aesasss l 5 Example are obtained if one uses 3-chloro-4-methylaniline or4- chloro-3-rnethylaniline in place of the dimethylaniline.

Example 16 /N HzN The procedure of Example 4 is followed using anequivalent quantity of beta-naphthylamine in place of Correspondingsubstituted compounds 'are obtained by using such derivatives asBronners acid, Dahls acid, amino J acid and amino G acid in place ofbeta-naphthylamine. V

7 Example 17 r 7 The procedure of Example 4 is followed using4-aminostilbene in equivalent quantities in place of the 4-aminol 5Example 19 HEN V To a hot well-stirred solution of 22.9 parts of thesodium salt of benzaldehyde ortho sulfonic acid and 16.2 parts ofS-nitro-orthotoluonitrile in parts of pyridine there is added 2 parts ofpiperidine and 9.2 parts of sodium bicanbona te. The mixture is heatedona steam bath until the reaction is substantially complete. During theheating period, an additional 40 parts of pyridine is added. The mixtureis then diluted with 200 parts of water and the pyridine is stripped outwith steam. The mixture is cooled with ice and the precipitated productis isolated by filtration and dried. a

To a vigorously stirred mixture of 29.5 parts of iron powder, 150 partsof Water and 4 parts of glacial acetic acid heated under reflux there isgradually added 11.8 parts of the product of the preceding paragraph.The mixture is heated under reflux with good stirring until the reactionis substantially complete and then is neutralized I with a small excessof soda ash. The iron sludge is filtered and Washed with hot methanoland the filtrate and washings are treated hot with charcoal. The mixtureis filtered and the filtrate is acidified with concentrated hydrochloricacid. The precipitated 4-amino-2-cyanostilbene-2'-sulfonic acid isisolated by filtration and purified by recrystallization from alcoholicmethanol followed by reprecipitation with hydrochloric acid.

An equivalent quantity of the above product is used in the procedure ofExample 2 in place of the 4-aminostilbene-Z-sulfonic acid used in thatexample.

Example 20 503E soan biphenyl. The product is a good brightener fornylon.

Example 18 N\ V V N CHZOH H2N r \N N CN' A mixture of 30 parts of2-cyano-4-nitrotoluene, 22

'parts of benzaldehyde and 5 parts of piperidine is heated at 125140 C;until the reaction is substantially com- The procedure of Example 2 isfollowed using an equivalent quantity of4-amino-4-nitrostilbene-2,2'-diplete. The melt is dissolved in160partsof hot glacial acetic acid and on cooling the crystalline solid whichforms is filtered. Toa boiling suspension of 9 parts of the aboveproduct in 250 parts of 95 7; alcohol is added a solution of 44 parts ofhydrated stannous chloride and 44 parts of concentrated hydrochloricacid. The mixture is heated at reflux temperature until reduction issubstantially complete. The mixture is then cooled and the solid isremoved by filtration.

It is purified by slurrying in dilute. sodium hydroxide solution.

'A solution of 4.4 parts of the 4-amino-2-cyano-stilbenes so produced in120 parts of acetic acid is prepared and to it is added 8.4 parts ofconcentrated hydrochloric acid. Twenty-two parts of N/l sodium nitritesolution is then added with cooling, and after stirring for a shortperiod the excess nitrite is discharged by the addition of sulfamicacid. The diazo solution is then used to couple with a solution of 3parts of 2,6-diaminopyridine in 100 parts of acetic acid, 100 parts ofwater. and 4 parts of concentrated. hydrochloric acid by the procedureof' Example 4. v v

sulfonic acid. The micro group is then reduced and -acylated as inExample 8, using benzoyl chloride.

7 Example 21 The procedure of Example 4 is followed using an equivalent'quantity of dehydrothioparatoluidine in place of the 4-aminodiphenyl. Asulfonated derivative of the above product is prepared'by following theprocedure of Example 2 and starting with an equivalent. quantity ofdehydrothioparatoluidine sulfonic acid in place of the aminostilbenesulfonic acid. 1

Example 22 equivalent quantity of 4'-amino-2-phenylbenzoxazole in placeof the, 4-aminodipheny1. V

equivalent quantity of 4f-amino-2-phenylbenzamidazole in place of the4-aminodiphenyl'. v V i Example 24 The procedure of Example 4 isfollowed using an equivalent quantity of S-aminobenzothiazole in placeof4-aminodiphenyl. Similarly, equivalent quantities of 5-amino-Z-methylbenzothiazole' and S-amino-Z-phenylbenzothiazole can beused to give the corresponding substituted products.

Example 25 g r v V 0 L N so HZN N/ o The procedure of Example 4 isfollowed using 6-amino- 2-phenj 1benzoxazole in equivalent quantities inplace of fl-aminodiphenyl. If 6-aminobenzo'xazo1e or 6-amino-2-methylbenzoxazole is used in equivalent quantities the correspondingbrightener compound is obtained.

Example26 N \c-0Ht The procedure of Example 4 is followed using anequivalent quantity of 5(6)-amino-2-methylbenzimidazole in place of4-aminodiphenyl; Y

The procedure of Example ll is followedusingan equivalent quantity ofbenzidine-2-sulfonic acid in place of diaminostilbene disulfonic acid; aJ I Examp' le28'i a The procedure of Example is followed using an 18equivalent quantity of 4,4-diaminostilbene in place of the benzidine.The corresponding monosulfonic acid is prepared if the procedure ofExample 11 is followed with 4,4-diarninostilbene monosulfonic acid.

7 Example 29 The procedure of Example 10 is followed using an equivalentquantity of 4,4-di-aminodiphenylamine in place of the benzidine. Thecorresponding n-alkyl compounds are prepared if equivalent quantities of4,4-diphenylmethylamine and 4,4', -d iphenylbutylamine are used' inplace of the 4,4'-diphenylamine above.

N/ n \N, NHI

' The procedure of Example 10 is followed using an equivalent quantityof 3,8-diaminodibenzothiophine-5,5'- dioxide in place of the benzidine.The corresponding sulfonated products are prepared by following theprocedure of Example 11 using as starting materials equivalent amounts.of 3,8-diaminodibenzothiophine-5,5-dioxide-2,7-disulfonic acid or thecorresponding monosulfonic acid.

1 Example 30 Example 31 The procedure of Example 10 is followed -usingan equivalent quantity of 4,4'-diaminodiphenylurea in place of thebenzidine. Example 32 The procedure of Example 9 is used using2-naphthylamine-S-sulfonic acid in place of naphthionic acid. Thecorresponding 'disulfonated product is obtained by using an equivalentquantity of 2-naphthylamine-4,6-disulfonic acid in place of thenaphthionic acid. If the naphthionic acid is replaced withbeta-naphthylamine the corresponding unsulfonated product is obtained. t

i Example 33 A mixture of 1. part of 5-amino-2-phenyl-(2)-pyridol2,3-d]-v-triazole (prepared as in Example 1), 40 parts .uct.

rat-m mmal and 44 parts of meth I iodide-is heated at the refluxtemperature until the reaction is completed, and is then evaporated todryness. The yellow solid which is obtainedgis purified by precipitatingfrom a methanol solution by the addition of diethyl' ether, giving onepart of white solid product which is soluble in water.

Similar quaternary derivatives are obtainedby the use of ethyl bromide,butyl bromide, benzyl chloride, 'allyl bromide, and ethylenechlorohydrin in placeof the methyl iodide, although the chlorides andbromides take a longer time to give complete reaction. In cases wherethe solubility properties of" the product were not sufliciently high;improved, characteristics may be obtained by metathetical exchangeof theanion to form the. corresponding acetate or nitrate or other salt.

" I V Y 'Example 3 4.

A mixture of 21 parts of 5-amino-2-phenyl (2).-pyrido- V.[2,3-d]-v-triazole, 24 parts of diethylsulfate and 100 parts of ethanolis heated at the reflux temperature until the reaction is. complete.

20 added dropwise with stirring? The mixture is stirred until thecoupling is completed. An orange product is filtered and 'allowed'todrain.

The product is taken up in 92' parts of ethanol, =16 parts of water,45.8 parts. by volume of concentrated ammonia and parts of pyridine andthe mixture is 7 The crystalline solid which forms is removed byfiltration.

- By using an equivalent'amount of dimethyl sulfate in 7 place of thediethyl sulfate, the corresponding methyl compound is obtained. a a

"A'mixture or 21 parts of 5-arnino- 2 ph'enyl-(2) pyrido- I tureuntil'th'e reaction is'co'mplete. After cooling, the solid is removedbyfiltration giving a water-soluble prod- WhenQthe methyl p-toluenesulfonate is replaced by an equivalent 7 amount of methyl'p-bromobenzene sulfonate the. corresponding p-bromoben'zene sulfonatesalt is obtained. J

' 7 Example 36 a for some fibers than does the product of Example 6 and7 on other fibers is. equivalent to the'unquaternized product.

Example 37 7 'N v V Br The diazonium solution from'0.03 mole o anilineis combined :with a chilled solution of 3.27; parts heated withstirring. A hot solution of 38.9 parts of copper sulfatein 1 15 parts.of water and 68.7 parts by volume of concentrated ammonia is added, a.stream of air is introduced, and the mixture is refluxed with stirringuntil the reaction isflsubstantially complete, it is cooled and theproduct is filtered, washed with water and dilute ammonia, dissolvedinhot dilute ethanolic hydrochloric acid, filtered hot withcharcoal andfiltered again. The clarified solution is left standing, and graduallyyields orange crystals. A hot dilute ethanolic solution of this productis clarified with charcoal made alkaline to phenolphtha'lein and treatedwith sodium hy osulfite at the boil. A shiny yellow product is 'filteredand dried at 60 C.

; Example 38 To 40 parts v=by volume of concentrated sulfuric acid isadded with stirring, 2.8 parts (0.04 mole) of finely ground sodiumnitrite, keeping the temperature below C. The resulting solution iscooled to 5 C.-, and a solution of 4.0 parts of 4-aminopyridine in 10parts of glacial acetic acid isadded dropwilse. at temperatures-below 15C. The mixture is stirred until'diazotization' is complete. Thediazonium solution is, combined, with ;a solution of 0.04 mole of2,6-diaminopyridine in 25 parts of glacial acetic acid at temperaturesbelow 15, C. 1 The brown solution is stirred until coupling is completeand then drowned on 30 parts of ice, and neutralized to pH of 7.8 withdilute caustic. The product is then filtered and dried andrecrystallized from absolute methanol.

dded to; [hot solution of The coupling product 1s .5.0 parts' of coppersulfate, 125 parts of'water and 25 parts of pyridine and the mixture isrefluxed'until the reaction is complete. It is then-v st'am stripped toremove the pyridine, acidified, cooled and' fi'ltered. The orangeproductis dissolved inhot dilute acid, filtered and dilute causticsolution is added to'precipitate theproduct. This is thendissolved inhot alcoholic H01 and precipitated -with concentrated ammonia to insureremoval of the copper ions. A cream'colore'd product is filtered, washedwater, and dried at 100 C.

-Exqmp An 0.005% solution of the hrightenerof Example 1 is prepared bydissolving .1 part of the brightener in 1000 parts of dimethyl formamide'at room temperature. This is then diluted with waterv containing asmall amount of dispersing agent (Triton X-100) to the 0.005% concen- V'tration. This; summ rs, used the following dyeing procedure: V E

To a mixture of '98,5.,parts ofwaterandlj parts of 10% acetic acidsolutionnisadded 50 parts'of 0.005% brightenersolution from above,A5-part piece of poly acrylonitrile fabric ,(Orlon) is added: and thetemperatureis raised to thfeboiling point-and held there for a about 30minutes. Thefabzic removed, rinsed in water and dried in the air. It ismuch whiter and brighter in 10 f nr-bromo- (0.03 mole) of2,6-diarninopyn'dine in 225 parts ofw'ate'r appearance than a piece ofthe untreated'Orlon fabric.

7 V V EJ cample 40 l An 0.005% solution of the brightener of Example 33is prepared by dissolvingl'ml'tof brightener in 1000 parts ofhoilingwater and diluting with water to the 0.005% concentration,

' To a mixture of 98.5 of water parts of Example 41 To a solution of0.025 part of the product of Example 1 is added 0.5 part of sodiumsulfate. A piece of cotton cloth weighing 5.0 parts is added and thedyebath is heated to 130 F. After minutes, another 0.5 part of sodiumsulfate is added and heating is continued for another 15 minutes. Thecloth is then removed, rinsed at 80 F., and dried. The dyed cloth isexposed to UV light in a darkroom. After removing the source of the UVlight it is observed that the emission of visible light continues for anoticeable period of time.

The dyed cloth is immersed in a 5% sodium hydroxide solution and steamedat one to two pounds pressure for 1 /2 hours. The cloth is then rinsedand immersed in a bleaching solution formulated with hydrogen peroxideand sodium silicate, after which it is then steamed again at one to twopounds pressure for one hour. After rinsing in dilute acetic acid andwater and then drying, the dyed cloth is again exposed to UV light.After the removal of the source of the UV light, the emission of visiblelight continues for a noticeable period, showing that the phosphorescentproperty of the cloth is retained after the above finishing treatments,typical of those to which fabrics are subjected in manufacture.

Example 42 /N\ N L X The procedure of Example 38 is followed using anequivalent quantity of S-aminopyrimidine in place of the4-aminopyridine. The product has the above formula.

We claim:

1. Compounds of the structure:

QQ & HaN KI N/ in which X is an anion and R is selected from the groupconsisting of lower alkyl, allyl hydroxyethyl and benzyl. 2. Thecompound 2-xenyl-6-amino-2,3-pyridotriazole. 3. The compound 2-(4-anisoylamidophenyl) -6-am=ino- 2,3-pyridotriazole.

References Cited in the file of this patent UNITED STATES PATENTS2,247,266 Pieter et al. June 24, 1941 2,527,314 Mackay Oct. 24, 19502,637,731 Vaughan May 5, 1953 2,638,403 Stead et al May 12, 19532,647,904 Rey-Bellet Aug. 4, 1953 2,750,385 Schmidle et al June 12, 19562,784,183 Keller et a1. Mar. 5, 1957 2,824,876 Katz et al. Feb. 25, 19582,845,425 Whitehead et al July 29, 1958 OTHER REFERENCES Bremer: Annalender Chemie, vol. 514, pages 280-82 and 290-91 (1934).

Charrier et al.: Gazz. Chirn. Ital, vol. 68, pages 640- 51 1938).

Chemical Abstracts, vol. 32, pages 6246-47 (1938).

Tinrmis et al.: Journal of Pharmacy and Pharmacology, vol. 9, pages 48and 58, January 1957.

1. COMPOUNDS OF THE STRUCTURE: